Stuart Miles, founder of technology and gadget site Pocket-lint, says he thinks the Facebook announcement will be the launch of an enhanced app for the social network.
My initial thought was that they couldn't possibly be launching a phone because that would be silly, because every phone is already a Facebook phone.
I think ultimately this will be an enhanced app that you can run from your homescreen on Android which will give you the feeling that your phone is a Facebook phone.
The launch of an "enhanced app" would reinforce Facebook's "mobile first" attitude, Miles added, as users increasingly monitor the social networking site from smartphones and tablets, rather than desktop computers.
More top news
Up until today Zurich has always been a safe haven for Fifa - an island could behave just how they wanted. Yesterday changed everything.
Prime Minister plans a whistle-stop charm offensive with EU leaders this week.
Thriller writer Anthony Horowitz is at the helm of the latest Bond book, which is based on an unfilmed Ian Fleming TV script.